Kayak has launched in the UK after weeks of quiet operation in "beta" phase. The website is well established in the US where it ranks eighth among travel agency sites, compared with 24th in the UK, according to internet monitoring agency Hitwise.

Kayak searches 404 websites to find airfares between any airport pair, as well as finding flights for multi-city trips (although Times Online Travel found that searches using this function don’t always return the best routing). You can search with a specific destination and date in mind or make your date and/or destination flexible to lower the cost of your flight. You can also limit searches by price, departure time and length of flight, to try to limit lengthy stopovers.

The "Buzz" section allows a flight search on terms as loose as London to Europe in February. The site then trawls through the relevant searches made by other users. This may sound limiting but when I tested the site it told me that over 1.7 million searches were being checked, and that 18,000 other “Kayakers” were online.

These registered users (registration takes only a couple of seconds), engage in lively forums, searchable by region, topic or keyword. The Forum is active, although most users are US-based. Some gems under discussion at the moment include entries on surfing in Nicaragua, advice from a sailing fanatic based in the Virgin Islands who answers questions on boating holidays, and exchanges between single travellers looking for a companion.

You can register to receive emails monitoring the fares on a specific route, or check the fare history using the graphic function that shows when fares were at their lowest in the past 90 days.

Flight comparison sites such as Yahoo Travel (19th), Skyscanner (16th), Cheapflights (8th) and Travelsupermarket.com (7th) still get more traffic than Kayak, but we predict it will climb up the ranks within weeks. It still owes much of its traffic to referrals – according to Hitwise, Kayak owes 54 per cent of its traffic for the week ending February 17 to Cheapflights, but this is likely to decrease once UK users become familiar with the site.

We love: the clean site and lack of ads; the fact that you can search for flights from multiple departure and arrival airports; the Buzz tool, which allows you to search for flights when you don’t have a specific place in mind and want to be inspired; the fact that prices includes taxes and fees; the slider tool that allows you to change flight times; the fare history graph.

We hate: the multi-city search won't always return the best routing, so best to check with a travel agent like Trailfinders before booking.

Verdict

Design: 7/10
Navigation: 8/10
Content: 9/10
Fulfilment: 8/10

Overall score: 32/40

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